ESD is a type of EMP.
An EMP is a Pulsed type of EMI.
And I think your question relates to Electromagnetic Compatibility system characteristics which is such a huge subject that it's most often managed rather than predicted (calculated).
As the frequency components (due to their pulsed nature, EMPs are broadband) are unknown at design time, you would have to assume the EMP contains DC to "daylight" frequency components. This means that an antenna's coupling would be irrelevant to the antenna's frequency characteristics and it's more directly related to the amplitude of the EMP.
I think basically you need to include sufficient EMI protection schemes to make sure any energy that makes it past ( shield, filters, transient absorbers, fuses, breakers ) are well below the component's operational limits.